Inventors Kit 9: Solar Powered Car
Posted by Matthew Little on
In this activity we are going to build a soalr powered car. This uses the motor to spins some wheels and make our car move!
The main issue with making our car is that the motor is not very powerful. This means we have to make sure the car is as efficient as possible and that any friction is low.
Friction is the resitance to motion. Try pushing different objects along the floor - some will be harder to push and some will be easier. If you push a large book along the floor then it might be quite difficult. If you push a toy car along the floor then it should be much easier. The wheels of the toy car can easily spin and so the friction is reduced.
You will need:
- Bamboo skewers
- Elastic band
- Cotton reel (empty, with no cotton)
- Jam jar lids x 2 - they must be the same size!
- Another jam jar lid
- Hammer and nail (ask an adult to help you with this)
- Cardboard and tape (as always!)
- Scissors
- Pen
Note: This might be the most complicated of the activities here - it certainly took me the most time to get it working! You might need some adult help to make this and get it running.
Sort out the main wheel: This is made from two jam jar lids with the cotton reel inbetween. Ask an adult to use the nail and hammer to make a small hold in the centre of each of the jam jar lids.
With the jam jar lids facing opposite directions, use tape to hold the cotton reel inbetween the two jam jar lids - this makes our single wheel which will be powered by the motor using an elastic band. We use a piece of bamboo skewer as the axle through the two jam jar lids and the cotton reel. Make sure the wheel spins easily on the bamboo skewer.
Cut the main body of the car out of thick cardboard:
I needed to add some stregtheners along the side of the cardboard base. My cardboard was quite thin:
Cut the motor holders: Make two triangles out of folded card. Tape them to the motor so that we can attach the motor to the carboard base.
Put an elastic band around the cotton reel and add the drive wheel to the cut out in the cardboard. The elastic band needs to be a thin one, just long enough to go around the cotton reel and stretched a bit to the motor spindle. You might need to try a few different ones to get it not too tight and not too loose!
Stick the motor down so the elastic band can go around the motor spindle with just a little be of tension. I needed to cut more f a hole out so the elastic band did not scrape on the cardboard base.
Sort out the front wheel: For the front wheel I used another jam-jar lid. Again, ask an adult to put a hole through the jam jar lid with a hammer and nail.
Again, use some bamboo skewer as an axle and tape to hold the axle in place. We need to make a cut in the front of the acrdboard base of the car that fits the wheel.
You might want to use two jam jar lids taped together, as mine was a bit wobbly!
Now we need to stick down the solar panel and take it into the sun for a test. It will need to be bright sunlight for this to work, as the motor needs a lot of power to spin the motor. You will also need to do this on a very flat surface, as any bumps wills top the wheels turning.
Note: If it's not sunny enough then you can use a battery, rather than the solar panel. You can use the motor circuit from the first activity (but I prefer the solar powered car!).
Here are some more learning resources and link for this activity: